1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
/*
* Makes a tree bootable image for IBM Evaluation boards.
* Basically, just take a zImage, skip the ELF header, and stuff
* a 32 byte header on the front.
*
* We use htonl, which is a network macro, to make sure we're doing
* The Right Thing on an LE machine. It's non-obvious, but it should
* work on anything BSD'ish.
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include <netinet/in.h>
#ifdef __sun__
#include <inttypes.h>
#else
#include <stdint.h>
#endif
/* This gets tacked on the front of the image. There are also a few
* bytes allocated after the _start label used by the boot rom (see
* head.S for details).
*/
typedef struct boot_block {
uint32_t bb_magic; /* 0x0052504F */
uint32_t bb_dest; /* Target address of the image */
uint32_t bb_num_512blocks; /* Size, rounded-up, in 512 byte blks */
uint32_t bb_debug_flag; /* Run debugger or image after load */
uint32_t bb_entry_point; /* The image address to start */
uint32_t bb_checksum; /* 32 bit checksum including header */
uint32_t reserved[2];
} boot_block_t;
#define IMGBLK 512
char tmpbuf[IMGBLK];
int main(int argc, char *argv[])
{
int in_fd, out_fd;
int nblks, i;
uint cksum, *cp;
struct stat st;
boot_block_t bt;
if (argc < 5) {
fprintf(stderr, "usage: %s <zImage-file> <boot-image> <load address> <entry point>\n",argv[0]);
exit(1);
}
if (stat(argv[1], &st) < 0) {
perror("stat");
exit(2);
}
nblks = (st.st_size + IMGBLK) / IMGBLK;
bt.bb_magic = htonl(0x0052504F);
/* If we have the optional entry point parameter, use it */
bt.bb_dest = htonl(strtoul(argv[3], NULL, 0));
bt.bb_entry_point = htonl(strtoul(argv[4], NULL, 0));
/* We know these from the linker command.
* ...and then move it up into memory a little more so the
* relocation can happen.
*/
bt.bb_num_512blocks = htonl(nblks);
bt.bb_debug_flag = 0;
bt.bb_checksum = 0;
/* To be neat and tidy :-).
*/
bt.reserved[0] = 0;
bt.reserved[1] = 0;
if ((in_fd = open(argv[1], O_RDONLY)) < 0) {
perror("zImage open");
exit(3);
}
if ((out_fd = open(argv[2], (O_RDWR | O_CREAT | O_TRUNC), 0666)) < 0) {
perror("bootfile open");
exit(3);
}
cksum = 0;
cp = (void *)&bt;
for (i=0; i<sizeof(bt)/sizeof(uint); i++)
cksum += *cp++;
/* Assume zImage is an ELF file, and skip the 64K header.
*/
if (read(in_fd, tmpbuf, IMGBLK) != IMGBLK) {
fprintf(stderr, "%s is too small to be an ELF image\n",
argv[1]);
exit(4);
}
if ((*(uint *)tmpbuf) != htonl(0x7f454c46)) {
fprintf(stderr, "%s is not an ELF image\n", argv[1]);
exit(4);
}
if (lseek(in_fd, (64 * 1024), SEEK_SET) < 0) {
fprintf(stderr, "%s failed to seek in ELF image\n", argv[1]);
exit(4);
}
nblks -= (64 * 1024) / IMGBLK;
/* And away we go......
*/
if (write(out_fd, &bt, sizeof(bt)) != sizeof(bt)) {
perror("boot-image write");
exit(5);
}
while (nblks-- > 0) {
if (read(in_fd, tmpbuf, IMGBLK) < 0) {
perror("zImage read");
exit(5);
}
cp = (uint *)tmpbuf;
for (i=0; i<sizeof(tmpbuf)/sizeof(uint); i++)
cksum += *cp++;
if (write(out_fd, tmpbuf, sizeof(tmpbuf)) != sizeof(tmpbuf)) {
perror("boot-image write");
exit(5);
}
}
/* rewrite the header with the computed checksum.
*/
bt.bb_checksum = htonl(cksum);
if (lseek(out_fd, 0, SEEK_SET) < 0) {
perror("rewrite seek");
exit(1);
}
if (write(out_fd, &bt, sizeof(bt)) != sizeof(bt)) {
perror("boot-image rewrite");
exit(1);
}
exit(0);
}
|
